From 4825ef699cda4c6f2f0586b17a5e225560481da6 Mon Sep 17 00:00:00 2001 From: Yafang Shao Date: Sun, 16 Aug 2026 17:04:41 +0800 Subject: klp-build: Fix wrong index in funcs cleanup error path In the object allocation loop, when kzalloc() for funcs fails, the cleanup loop uses `objs[i].funcs` instead of `objs[j].funcs`. Since `objs[i].funcs` is still NULL at that point, it repeatedly calls kfree(NULL) and leaks all previously allocated funcs arrays. Fixes: 59adee07b568 ("livepatch/klp-build: Add stub init code for livepatch modules") Signed-off-by: Yafang Shao Acked-by: Song Liu Reviewed-by: Petr Mladek Acked-by: Miroslav Benes Link: https://patch.msgid.link/20260816090442.18128-2-laoar.shao@gmail.com Signed-off-by: Josh Poimboeuf --- scripts/livepatch/init.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'scripts') diff --git a/scripts/livepatch/init.c b/scripts/livepatch/init.c index f14d8c8fb35f..16aff8f736eb 100644 --- a/scripts/livepatch/init.c +++ b/scripts/livepatch/init.c @@ -51,7 +51,7 @@ static int __init livepatch_mod_init(void) if (!funcs) { ret = -ENOMEM; for (int j = 0; j < i; j++) - kfree(objs[i].funcs); + kfree(objs[j].funcs); goto err_free_objs; } -- cgit v1.2.3 From 06bb43d8c79762fa3452f292cd080e54bef5d431 Mon Sep 17 00:00:00 2001 From: Vlad Poenaru Date: Wed, 2 Sep 2026 09:13:47 -0700 Subject: kbuild: don't delete in-flight filechk temporaries in asm-headers MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Commit 2d69b891e646 ("kbuild: Support generated asm-headers in subdirectories") switched the stale-wrapper sweep in scripts/Makefile.asm-headers from $(wildcard $(obj)/*.h) to a find(1) invocation, so that generated headers in subdirectories are considered. The two do not match the same set of files. Make's $(wildcard) uses glob semantics, where a leading '.' has to be matched explicitly, whereas find's -name uses fnmatch() without FNM_PERIOD, so '*.h' matches dotfiles as well. filechk writes its output to $(dir $@).tmp_$(notdir $@) before renaming it into place, so such a scratch file, if it happens to exist in $(obj) when the sub-make is parsed, is now picked up in old-headers. It appears in neither generic-y, generated-y nor syscall-y, is therefore classified as unwanted, and cmd_remove deletes it. On x86 this races with archprepare, which lists both asm-generic and arch/x86/include/generated/asm/cpufeaturemasks.h as prerequisites. Under -j they run concurrently against the same directory, and the build fails intermittently: mv: cannot stat 'arch/x86/include/generated/asm/.tmp_cpufeaturemasks.h': No such file or directory make[1]: *** [arch/x86/Makefile:269: arch/x86/include/generated/asm/cpufeaturemasks.h] Error 1 The same commit also converted the generic wrapper rule to filechk, so those wrappers now create .tmp_*.h in $(obj) too and can race among themselves. Restore the previous behaviour by excluding dotfiles from the sweep. Subdirectories, which is what the find(1) conversion was for, keep being descended into. While at it, quote the -name argument: it is currently expanded by the shell against the build directory before find sees it. Fixes: 2d69b891e646 ("kbuild: Support generated asm-headers in subdirectories") Signed-off-by: Vlad Poenaru Reviewed-by: Nathan Chancellor Reviewed-by: Thomas Weißschuh Reviewed-by: Nicolas Schier Link: https://patch.msgid.link/20260902161347.4163577-1-vlad.wing@gmail.com Signed-off-by: Nicolas Schier --- scripts/Makefile.asm-headers | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'scripts') diff --git a/scripts/Makefile.asm-headers b/scripts/Makefile.asm-headers index b38931314ad7..f1c3d287c14b 100644 --- a/scripts/Makefile.asm-headers +++ b/scripts/Makefile.asm-headers @@ -48,7 +48,7 @@ syscall-y := $(addprefix $(obj)/, $(syscall-y)) generated-y := $(addprefix $(obj)/, $(generated-y)) # Remove stale wrappers when the corresponding files are removed from generic-y -old-headers := $(shell test -d $(obj) && find $(obj) -name *.h) +old-headers := $(shell test -d $(obj) && find $(obj) -name '*.h' ! -name '.*') unwanted := $(filter-out $(generic-y) $(generated-y) $(syscall-y),$(old-headers)) filechk_wrap = echo "\#include " -- cgit v1.2.3 From 4f73462856576797b8f3c55564a9be99f76dc67b Mon Sep 17 00:00:00 2001 From: Nathan Chancellor Date: Mon, 31 Aug 2026 18:46:31 -0700 Subject: scripts/sorttable: Mark long_size as __maybe_unused When building in a kernel tree prior to commit b055f4c431e3 ("sorttable: Move ELF parsing into scripts/elf-parse.[ch]") with clang-23 or newer, which implements a new warning under -Wunused-but-set-variable for static global variable, there is a warning from sorttable because long_size is unused when MCOUNT_SORT_ENABLED is not set: scripts/sorttable.c:452:12: error: variable 'long_size' set but not used [-Werror,-Wunused-but-set-global] 452 | static int long_size; | ^ Mark long_size as __maybe_unused to avoid inserting more ugly #ifdef directives while insuring the warning does not reappear, as the aforementioned change does not alter the uses of long_size, so it appears to be coincidence that the warning disappears after this refactoring. Cc: stable@vger.kernel.org Signed-off-by: Nathan Chancellor Tested-by: Nicolas Schier Link: https://patch.msgid.link/20260831-sorttable-long_size-unused-but-set-global-v1-1-8a96b88697e5@kernel.org Signed-off-by: Nicolas Schier --- scripts/sorttable.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'scripts') diff --git a/scripts/sorttable.c b/scripts/sorttable.c index d8dc2a1b7c31..d7b50581c732 100644 --- a/scripts/sorttable.c +++ b/scripts/sorttable.c @@ -116,7 +116,7 @@ static inline void *get_index(void *start, int entsize, int index) } static int extable_ent_size; -static int long_size; +static int long_size __maybe_unused; #define ERRSTR_MAXSZ 256 -- cgit v1.2.3 From 281b61d408d4c39544583e393c6707af0ef5ee50 Mon Sep 17 00:00:00 2001 From: "Lorenzo Stoakes (ARM)" Date: Tue, 8 Sep 2026 21:55:01 +0100 Subject: scripts/mksysmap: drop the MODULE_INFO() symbols from kallsyms Commit 3e86e4d74c04 ("kbuild: keep .modinfo section in vmlinux.unstripped") keeps .modinfo symbols out of System.map and kallsyms, which assumes unique IDs have a format like '__UNIQUE_ID_modinfo123'. However, commit afb026b6d35c ("compiler: Tweak __UNIQUE_ID() naming"), sent in the same cycle, changes this to '__UNIQUE_ID_modinfo_123'. As a result this regexp has never matched and every kernel since v6.18 has carried one kallsyms entries for every MODULE_INFO() declaration in the kernel whether the modules are compiled or not. That's 5,810 entries for an x86 defconfig build and 15,200 for arm64. On x86 defconfig that is 113 KiB of kallsyms tables and 32 KiB of bzImage, and every lookup walks past them. Fix the pattern. Fixes: 3e86e4d74c04 ("kbuild: keep .modinfo section in vmlinux.unstripped") Assisted-by: LLM Signed-off-by: Lorenzo Stoakes (ARM) Reviewed-by: Nicolas Schier Reviewed-by: Nathan Chancellor Link: https://patch.msgid.link/20260908-build-speedup-v1-1-5dc1ac01672d@kernel.org Signed-off-by: Nicolas Schier --- scripts/mksysmap | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'scripts') diff --git a/scripts/mksysmap b/scripts/mksysmap index c4531eacde20..56a8b8bbdb37 100755 --- a/scripts/mksysmap +++ b/scripts/mksysmap @@ -83,7 +83,7 @@ / _SDA2_BASE_$/d # MODULE_INFO() -/ __UNIQUE_ID_modinfo[0-9]*$/d +/ __UNIQUE_ID_modinfo_[0-9]*$/d # --------------------------------------------------------------------------- # Ignored patterns -- cgit v1.2.3 From 59351365ac271b5e0eb180f211c531476a36221f Mon Sep 17 00:00:00 2001 From: "Lorenzo Stoakes (ARM)" Date: Tue, 8 Sep 2026 21:55:02 +0100 Subject: scripts/mksysmap: fix escape of '$' in the __pi_ pattern Commit b18b047002b7 ("kbuild: change scripts/mksysmap into sed script") converted scripts/mksysmap from a shell script to a sed script. However an error was made - escaping of '$' required \\ escaping in shell but only \ in a sed script. This was mostly corrected in commit 7a6c355b55c0 ("scripts/mksysmap: Fix escape chars '$'"), but this fix missed arm64 PIE namespace local symbols like __pi_$x and __pi_$d which appear in System.map and /proc/kallsyms: $ grep __pi_\\$ /proc/kallsyms | sort -u 0000000000000000 d __pi_$d 0000000000000000 t __pi_$x Fix the escaping properly. Fixes: b18b047002b7 ("kbuild: change scripts/mksysmap into sed script") Assisted-by: LLM Signed-off-by: Lorenzo Stoakes (ARM) Reviewed-by: Nathan Chancellor Reviewed-by: Nicolas Schier Link: https://patch.msgid.link/20260908-build-speedup-v1-2-5dc1ac01672d@kernel.org Signed-off-by: Nicolas Schier --- scripts/mksysmap | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'scripts') diff --git a/scripts/mksysmap b/scripts/mksysmap index 56a8b8bbdb37..856b26ba2ac0 100755 --- a/scripts/mksysmap +++ b/scripts/mksysmap @@ -35,7 +35,7 @@ / __efistub_/d # arm64 local symbols in PIE namespace -/ __pi_\\$/d +/ __pi_\$/d / __pi_\.L/d # arm64 local symbols in non-VHE KVM namespace -- cgit v1.2.3 From 63edf5a009ae366369a1b484cd9ae4ee7c51946c Mon Sep 17 00:00:00 2001 From: "Chang S. Bae" Date: Wed, 16 Sep 2026 23:00:03 +0000 Subject: x86/build/64: Prevent native builds from generating EGPR use Omar reports that CONFIG_X86_NATIVE_CPU=y allows builds to opportunistically emit instructions using %r16-%r31 (EGPRs) when the build host supports APX since the commit: ea1dcca1de12 ("x86/kbuild/64: Add the CONFIG_X86_NATIVE_CPU option to locally optimize the kernel with '-march=native'") But the kernel is not yet prepared to use new registers internally. For example, there is no context-switch support for general in-kernel use. Explicitly disable EGPR use when building with -march=native. For C, since GCC 14 and Clang 18, both compilers support suppressing EGPR use with -mno-apx-features=egpr, whose availability can be detected via cc-option. For Rust, pass features=-apxf through the generated JSON to avoid unstable-feature warnings, see https://github.com/rust-lang/rust/issues/139284 Note Rust only accepts the option to disable APX instructions entirely or not. Support for this gating also depends on the Rust/LLVM combination. Rust 1.88 introduced the `apxf` feature option, but versions prior to 1.93 may emit an `apxf` attribute to the backend that only LLVM 23 or later can interpret. Restrict native Rust builds accordingly. Fixes: ea1dcca1de12 ("x86/kbuild/64: Add the CONFIG_X86_NATIVE_CPU option to locally optimize the kernel with '-march=native'") Reported-by: Omar Avelar Signed-off-by: Chang S. Bae Signed-off-by: Borislav Petkov (AMD) Reviewed-by: Nathan Chancellor Acked-by: Miguel Ojeda Cc: stable@vger.kernel.org Link: https://patch.msgid.link/20260916230003.1144622-1-chang.seok.bae@intel.com --- arch/x86/Kconfig.cpu | 11 +++++++++++ arch/x86/Makefile | 5 +++++ scripts/generate_rust_target.rs | 5 +++++ 3 files changed, 21 insertions(+) (limited to 'scripts') diff --git a/arch/x86/Kconfig.cpu b/arch/x86/Kconfig.cpu index e4654388d794..6e7a366f0798 100644 --- a/arch/x86/Kconfig.cpu +++ b/arch/x86/Kconfig.cpu @@ -204,10 +204,21 @@ config CC_HAS_MARCH_NATIVE # usage warnings that only appear wth '-march=native'. depends on CC_IS_GCC || CLANG_VERSION >= 190100 +config RUSTC_HAS_APXF + # The kernel isn't ready for in-kernel APX instructions. Without + # explicit frontend gating of APX, the backend may emit those + # instructions in native builds. + # + # Rust 1.88 added the `apxf` feature option, but versions before 1.93 + # emit an `apxf` target attribute that only LLVM 23+ can interpret. + def_bool (RUSTC_VERSION >= 108800 && RUSTC_LLVM_MAJOR_VERSION >= 23) || \ + RUSTC_VERSION >= 109300 + config X86_NATIVE_CPU bool "Build and optimize for local/native CPU" depends on X86_64 depends on CC_HAS_MARCH_NATIVE + depends on !RUST || RUSTC_HAS_APXF help Optimize for the current CPU used to compile the kernel. Use this option if you intend to build the kernel for your diff --git a/arch/x86/Makefile b/arch/x86/Makefile index 598f178102ee..8af6b80cffdd 100644 --- a/arch/x86/Makefile +++ b/arch/x86/Makefile @@ -161,6 +161,11 @@ else ifdef CONFIG_X86_NATIVE_CPU KBUILD_CFLAGS += -march=native + # Prevent the compiler from generating EGPR use. The kernel is + # not yet prepared for general in-kernel use. + KBUILD_CFLAGS += $(call cc-option,-mno-apx-features=egpr) + + # generate_rust_target.rs handles Rust APX gating. KBUILD_RUSTFLAGS += -Ctarget-cpu=native else KBUILD_CFLAGS += -march=x86-64 -mtune=generic diff --git a/scripts/generate_rust_target.rs b/scripts/generate_rust_target.rs index 3bf296581a88..7687b0dd5474 100644 --- a/scripts/generate_rust_target.rs +++ b/scripts/generate_rust_target.rs @@ -224,6 +224,11 @@ fn main() { features += ",+harden-sls-ijmp"; features += ",+harden-sls-ret"; } + if cfg.has("X86_NATIVE_CPU") { + // Prevent the backend from generating APX instructions. The kernel is not yet prepared + // for general in-kernel EGPR use. + features += ",-apxf"; + } ts.push("features", features); ts.push("llvm-target", "x86_64-linux-gnu"); ts.push("supported-sanitizers", ["kcfi", "kernel-address"]); -- cgit v1.2.3